Instruction manual

Issue H Oct 04
PAGE
42
GV Dry Vacuum Pumps
MAINTENANCE
42
The pump-motor trips out due
to excessive electrical current
consumption when the GV250
pump is operating with pump-
inlet pressure in the range 300
to 1000 mbar (3.0 x 10
4
to
1 x 10
5
Pa, 225 to 750 torr),
or when the GV400 pump is
operating with pump-inlet
pressure in the range 200 to
1000 mbar (2.0 x 10
4
to
1 x 10
5
Pa, 150 to 750 torr)
Is the interstage relief valve
stuck in the closed
position ?
Inspect the valve and if necessary replace it:
refer to Section 5.10.
The gearbox and oil are
contaminated with the process
substances pumped.
Has the shaft-seal purge
failed ?
Check the pressure of the air or nitrogen
purge flow to the shaft-seals; if necessary
adjust the air or nitrogen pressure. Change
the gearbox oil before you restart the
pump (refer to Section 5.7).
Have the seals in the pump
failed ?
The seals must be replaced. Contact your
supplier or BOC Edwards for advice.
The gearbox is noisy. Is the oil level low ? Check the oil level and fill as necessary
(refer to Section 5.3).
The pump does not operate. Is the pump-motor faulty ? Make all the other appropriate checks in
this table. If there is no other apparent
cause for failure of the pump to operate,
check the pump-motor and if necessary
replace it (refer to Section 5.11).
- - If you cannot rectify a problem, or if you
cannot identify the cause of a problem,
contact your supplier or BOC Edwards for
advice.
Symptom Check Actions
Table 15 - Fault finding (Sheet 2 of 2)